Machine for cutting precious stones



Aug. 16, 1966 v 1 sw 3,256,476

MACHINE FOR CUTTING PRECIOUS STONES Filed Feb. 17, 1964 2 Sheets-Sheet 1Aug. 16, 1966 J. SWAAB 3,266,476

- MACHINE FOR CUTTING PRECIOUS STONES Filed Feb. l7, 1964 2 Sheets-Sheet2 FIG.2

United States Patent 3,266,476 MACHINE FOR CUTTING PRECIOUS STONES JackSwaab, 493 Whitewood Road, Englewood, NJ. Filed Feb. 17, 1964, Ser. No.345,385 2 Claims. (Cl. 12530) My invention relates to machines forcutting precious stones particularly diamonds.

Known machines of said type comprise a cutting disk rotatable about ahorizontal axis and a stone holder which clamps the stone to be cut andwhich is held in operational position relative to the cutting disk by aswingable support arm. The swing movement of this arm is governed bycontrol means which adjust the position of the arm and thus of the stoneprior to and during the cutting operation relative to the cutting disk.In one known machine said control means comprise a vertical adjustingspindle screwed into said arm and resting upon a resilient support; inanother known machine a threaded spindle screwed into the support armrests upon the machine frame and while being slowly rotated swings thesupport arm and the stone clamped in its holder against the cutting diskholding the stone in constant operational position.

The said and other known control means to govern said movement of thesupport arm and thus of the stone holder did not permit a regulation ofthe speed and extent of said movement and its adaptation to thepeculiarities of the stone to be cut.

The object of my invention is to avoid the said and other disadvantagesof the known machines and more particularly to improve the said controlmeans.

According to my invention the improved control means comprise a straphinge member composed of an upper and a lower flap or leaf and aconnecting hinge. The strap hinge member rests with its lower flap uponthe machine frame and is displaceable in a direction perpendicular tothe axis of the hinge. The above mentioned adjusting spindle for theswingable support arm rests upon the upper flap and follows the samewhen it is turned over the hinge axis.

It will be understood that any above indicated displacement of the straphinge member in a direction at least substantially perpendicular to thehinge axis will cause the adjusting spindle to rest upon the upper flapat different distances from the hinge axis so that the support arm andthus the stone holder will perform movements of different extent andspeed when appropriate driving and actuating means cause during thecutting operation a continuous angular displacement of the upper flap.

The said and other objects of my invention will be more fully understoodfrom the following specification when read with the accompanying drawingshowing one embodiment of my improved machine for cross-cutting preciousstones particularly diamonds.

In the drawing:

FIG. 1 is a perspective view of the machine,

FIG. 2 is a partial sectional view along line 2 -2 of FIG. 1,

FIG. 3 is a cross section along line 33 of FIG. 2,

FIG. 4 is a partial sectional view similar to FIG. 2, and

FIG. 5 is a side view, partly in section, in the direction of arrow 5 inFIG. 1.

The same reference numerals indicate the same parts in all figures.

The machine illustrated in the drawing comprises a base frame 11 whichis properly secured to work table 12. Mounted in the forward portion ofsaid frame is a cutting disk 13 which is rotatable upon a horizontalaxis and driven in any suitable manner for instance by the 3,266,476Patented August 16, 1966 belt 14 engaging the pulley 15. The stone suchas a diamond 16 to be cut is clamped in a stone holder 17 which iscarried in the forked end of the double arm 18 which is pivot-ablymounted in brackets 19 of frame 11. The other end of said arm 18 carriesan adjustable counterbalance weight 20 which controls the pressurebetween the cutting disk 13 and the stone 16 resting thereupon.

While. the machine elements described before are known in the art, mypresent invention relates in particular to the control means whichgovern the downward movement of the stone 16 while the same rests uponand is being cut by the rotating cutting disk 13. These improved controlmeans permit to easily change, and adapt to the existing particularitiesof the stone to be cut, the extent and the speed of said downwardmovement.

According to my invention, I provide a strap hinge member composed oftwo elongated flaps or leaves 21, 22 which are jointed by a hinge 23.The said strap hinge member rests with its lower flap 21 upon the frame11 and is displaceable in a direction perpendicular to the axis of thehinge 23 as indicated by arrow 30 in FIG. 1. The lower flap 21 issecurable to the frame 11 in any adjusted position by the clip 26 or byany equivalent element and carries at its free end a casing 24, whichhouses an electric motor with suitable transmission means driving ascrew 25. This screw passes freely through both flaps 21, 22 and engagesan intermediately thereof located washer or nutlike member 27 whichsupports the upper flap 22. The washer 27 is secured against rotationfor example by the tongue 28 which abuts against a side face of the'flap 22. It will be understood that the screw 25 when rotated causesthe engaged washer 27 to move upward or downward forcing thereby theupper flap 22 to turn accordingly about the hinge 23.

The arm 18 is provided with an adjusting screw 29 which rests with itsfree end upon the upper flap 22.

My machine operates as follows:

Before the cutting operation on the stone 16 is started the flaps 21, 22are in a position approximately shown in FIG. 4. The adjusting spindle29 resting upon the upper flap 22 is so adjusted that the arm 18 bringsthe stone 16 into an operational starting position relative to thecutting disk 13 and the strap hinge member is displaced in eitherdirection indicated by arrow 30 to regulate the extent and speed of thedownward movement of the adjusting screw 29; thus the required extentand speed of the downward movement of the arm 18 with stone 16 is alsoset during the cutting operation. After the said adjustments have beenmade the motor in casing 24 rotating the screw 25 and the driving meansfor the cutting disk 13 are started and the stone 16 will slowly andcontinuously be out.

Although only one form of my improved machine has been shown anddescribed by way of illustration, it will be understood that it may beconstructed in various other embodiments which do not depart from theprinciples of my invention and come within the scope of the appendedclaims.

What I claim as my invention is:

1. In a cutting machine for precious stones such as diamonds theimprovement comprising in combination a stationary frame; a cutting diskmounted in the frame rotatably about a horizontal first axis; a supportarm mounted in the frame swingably about a horizontal second axis; astone holder held in the support arm in operational relation to thecutting disk; a strap hinge member including an upper flap articulatedto a lower flap; said strap hinge member resting with its lower flapupon the frame shiftably in a direction substantially perpendicular tothe articulation axis and perpendicular to said arm;

securing means to fix said lower flap to the frame in any of its shiftedpositions; an adjusting spindle screwed into said support arm andresting with its operational end upon said upper flap to set saidsupporting arm with the stone holder into starting operational relationto the cutting disk; and actuating means for the turnable upper flapcausing the same to gradually approach the lower flap during the cuttingoperation, thereby causing the stone holder to uniformly approach thecutting disk during the progressing cutting operation.

2. In a cutting machine according to claim 1 actuating means for theupper flap comprising a substantially vertical rotatable screw memberfreely penetrating the two flaps near their free ends and a nonrotatablenut 4 .t guiding the upper flap during its gradual approach towards thelower flap.

References Cited by the Examiner UNITED STATES PATENTS member engaged bysaid screw member supporting and 15 HAROLD D. WHITEHEAD, PrimaryExaminer.

1. IN A CUTTING MACHINE FOR PRECIOUS STONES SUCH AS DIAMONDS THEIMPROVEMENT COMPRISING IN COMBINATION A STATIONARY FRAME; A CUTTING DISKMOUNTED IN THE FRAME ROTATABLY ABOUT A HORIZONTAL FIRST AXIS; A SUPPORTARM MOUNTED IN THE FRAME SWINGABLY ABOUT A HORIZONTAL SECOND AXIS; ASTONE HOLDER HELD IN THE SUPPORT ARM IN OPERATIONAL RELATION TO THECUTTING DISK; A STRAP HINGE MEMBER INCLUDING AN UPPER FLAP ARTICULATEDTO A LOWER FLAP; SAID STRAP HINGE MEMBER RESTING WITH ITS LOWER FLAPUPON THE FRAME SHIFTABLY IN A DIRECTION SUBSTANTIALLY PERIPENDICULAR TOTHE ARTICULATION AXIS SAID LOWER FLAP TO THE FRAME IN ANY SECURING MEANSTO FIX SAID LOWER FLAP TO THE FRAME IN ANY OF ITS SHIFTED POSITIONS; ANADJUSTING SPINDLE SCREWED INTO SAID SUPPORT ARM AND RESTING WITH ITSOPERATIONAL END UPON AND UPPER FLAP TO SET SAID SUPPORTING ARM WITH THESTONE HOLDER INTO STARTING OPERATIONAL RELATION TO THE CUTTING DISK; ANDACTUATING MEANS FOR THE TURNABLE UPPER FLAP CAUSING THE SAME TOGRADUALLY APPROACH THE LOWER FLAP DURING THE CUTTING OPERATION, THEREBYCAUSING THE STONE HOLDER TO UNIFORMLY APPROACH THE CUTTING DISK DURINGTHE PROGRESSING CUTTING OPERATION.